With a rapid development of touch screen, current mainstream products mostly adopt a touch screen in which a touch panel is directly added to a surface layer of display panel (Add On structure). However, such a conventional Add On touch screen is heavy and thick, and has higher cost. With the consumer's demand for a lighter and thinner touch screen, in-cell touch screens become important development direction in the touch screen field.
In a conventional in-cell touch screen, both of driving electrode and sensing electrode are designed within the liquid crystal panel. The driving electrodes adopt shared common electrodes, thus each of the common electrodes acts as one driving electrode. Sensing electrodes are formed on inner side of an opposing substrate and at positions opposite to black matrix. Although the sensing electrodes designed as described above have sensing function, load and node capacitance of the sensing electrodes could not be in an appropriate range for fulfilling the integrated circuit standard due to limitations in manufacturing process, thus the performance of the touch screen is deteriorated.